[Dave Goob Cook]

Gotta have full stroke.
Full bottom and full return first and foremost, with positive retention of the pushrod in the M/C please!!!!!

No need for the valving, but it won't kill ya either.....

Any factory valves have been removed, correct?

M/C is higher than the calipers?
Lines need to not run "up" at any point out of the M/C. (Line-Lock or pressure gauge plumbing?)

Bench bleed, install M/C keeping the outlets turned "up" as much as possible, while you finger in the lines, mount it, leave the lines cracked just a touch while an assistant strokes the pedal all the way down and holds it, while you snug the lines. Then gravity bleed it at all 4, shut off as fluid flows to each one, then start a "normal" bleed process.

Sometimes if the lines have been flushed or dry, you should open all bleeders, stroke the pedal full down and hold, close bleeders, let pedal up, repeat as needed, to get as much air out initially as possible.

I've had to do brakes alone for years, found some tricks. I've replaced many M/C's without the need for any bleeding, only flushing out of the old fluid....
Speaking of that, the lines were clear and dry, no kinks or dents, no excess moisture around when the system was open?
Any possibility of fluid contamination?

Remember that some braided steel lines (non hard Teflon liner) will give you a spongy pedal, and the brake pedal never feels "hard" enough until the new pads/shoes are bedded in properly.

IF you are using a Silicone fluid, there are more details to follow.
Been there, done that, nothing wrong with it at all, you just have to treat it differently.

I like Valvoline Synpower brake fluid.