The manual is stating to us "lrt-12-90 " to align the keyway. Any videos i see do not seem to have issue aligning nor do they use the tool. I will probably replace the front seal while I'm there. Is there a chance of struggle aligning key or should it stay pretty straightforward? All my experience is with 2.25 rover engines
There is clearance between the bolt shanks and holes in the timing cover. You best should align this cover with a sleeve that slides over the crank snout (slide fit no clearance) with the OD a slide fit (no clearance) into the timing cover's ID bore near the seal. This way the seal along with oil pump ID gear bore is concentric with the crank preventing an early seal failure and leaks. Alignment reduces uneccessary sliding action with the oil pump gear and the crank drive system. Should this alignment be off more than the clearance of the pump gear to crank you then added a side force with the pump gear now applied against the pump's outer ring, and a ticking time bomb.
I wouldn't start an engine assembled without the housing not being concentric aligned including ""eyeball aligned".
You checked the timing housing on a flat surface like a table saw or a granite surface used in (good) machine shops as the housing ma also now be warped if you must reuse the old timing cover?
High mileage engines the pressure relief plunger of machined hardened steel cycling back and forth inside the aluminum bore will have worn the bore allowing the plunger to possibly stick in the open "bypass position" hence lower oil pressure once the oil has heated up and is now thinner at operating temps. Multi Viscosity oil can only go so far in thickening as temps rise also breaking down over time and mileage.
I recall $680 LR OEM replacement cost the timing cover back in 11/01, extended warranty didn't want to pay for replacement cover going onto a factory new 4.6 shortblock. I wanted in writing I receive a new second 4.6 should the old timing cover fail again. This plus legal action resolved this issue as the old timing cover had a sticking bypass issue with low oil pressures not noted by the "idiot light" but by the pressure gauge I installed.
This the reason why the POS 3.9 was injured having low oil pressure issues.
Worn rockers and shafts along with LR's cams and lifters, link belt timing belt and gear sets of low quality materials, dealing with a high mileage engine of only 60-75K miles items above starting to fail.
Bad enough morning dry starts long with the high inital rpm's. Cold start after an oil and filter change WAS CRINGE WORTHLY before modifications added before the 4.6 installed. Heads another issue LR's failed patch jobs.
Restricted IAC line along with 3 qt. MasterLube.org Pre-Oiler, engine has 38 psi oiling before crank rotates along with a 875 rpm cold start fast idle. Dripping wet internally the crank now slings oil up into the cylinder bores lubing them vs dry from overnight drain down.
Best insurance to add a oil pressure gauge vs that "idiot light", switch allowing checking engine as well Pre-Oiler accumulator pressure.
With modified "Sandwich adapter" run a longer 7" long oil filter that alone holds 34 ounces oil a lot more filtering surface area, less pressure drop across the filter plus increased ability to not go into "bypass" on cold start with thick cold oil. This bypass happens with idiots revving their cold engines.
Diehard LR pushrod engine person going back to the 60's these Buick Olds GM engines.
Several details and attention can wake up these engines like simple port matching along vs LR's sick ugly misalignments they produced and assembled, not talking any radical porting jobs. ECU chip another big wakeup allowing proper fueling these engines that still pass Kalifornia's SS patrolled smog inspections.
Above advice costing you two large fresh packed in ice Maine lobsters.....~~=o&o>......