Here's my experience ...
ANY aluminum cover is going to bind with the "stock" torques specs. Not only have I used a couple different aluminum covers but will point out that virtually EVERY used cover you see at swap meets will show significant wear in the cover. This is despite them supposedly being "hard anodized".
What I've started doing is assembling them on a bench with plain nuts and bolts (grade 5). Start by measuring the depth of the pump body and the height of the rotor and stator - make sure there will be clearance once the cover is installed. You want some clearance but no more than .0015. The FSM gives the specs. Now start torqueing the bolts. At about 15 pounds check that the pump spins freely, If so, bump up the torque to 20 and check again. Do this till a) the pump binds or b) you get to 35 foot pounds.
I currently have one that binds at any more than 15 foot pounds ! The bolts are in with lots of red loctite !!
Good luck. I have 2 engines using the full billet Milodon pumps, I'm pretty sure I torque them to less than 15 lb/ft, like you I keep checking the bind with a priming tool by hand 'till I feel it start to bind. IIRC it's around 12 lb/ft with lots of loctite. Luckily we've never had a problem with leaks or anything coming loose.
'74 Challenger..9.46 @ 145.9 1/4, 6.001 @ 118 1/8 so far. 4023lb !!! # N/A, Marsh performance 655ci, Indy Maxx, T/R, Indy 600-13 X's, Street legal, pump gas, full interior, Cal-Tracs, mufflers, 3:73's and real 10.5 radials.
9.51 @ 142.4 1/4, 6.003 @ 114 1/8 with our old mule KB, 572-13, 580 wedge.
RHD '68 Barracuda Fastback 323ci street/strip. Best ET 13.88 @ 99.03
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