Continued on with the 'gentrification' by dropping in a new brake booster & master cylinder. Not that it necessarily needed it worth replacing after 20+ years of service since it was the last untouched component that could have been responsible for a suspected slight vacuum leak. Went with an OE ATE booster with a Febi master cylinder. Would have loved an ATE unit for the latter as well but unfortunately it was backordered, as were all other variants apart from the Febi one on Spareto and I wasn't keen on a 28 day wait. Febi obviously used a different casting method than the original but didn't look too bad quality wise. I guess time will tell as to its longevity.
Transferred over the sensors, hoses and reservoir. I flushed the brake fluid when doing the engine swap and it still looked fresh up top, until I removed the strainer tube that revealed a puddle of black sludge sitting at the bottom of the reservoir. Glad to have all that washed out.
With the booster disconnected I used the opportunity to easily take out the pedal box and change out the plastic pedal bushes. I hadn't thought of getting new ones at the time of the swap but did get a fresh set in the meantime, was just waiting for a chance to drop them in. I hadn't noticed any issues during normal operation but did notice the clutch pedal having some excessive side-to-side play when removing it, something that the new bushes tightened right up.
The bleeding procedure was made infinitely easier by the cheapo pressure bleeder kit I picked up recently. Best $100 ever spent! Made the whole process an absolute breeze even as a one-man-band. Got the major bubbles out on all 4 corners, then ran the ABS bleeding procedure through INPA by routing my dedicated scanning laptop under the car using a bunch of USB cable extensions and bleeding the brakes through thoroughly once more. Then did the clutch and job's a good 'un.
Whilst under there, I also drained the ATF from the gearbox and replaced it with some Redline MTL that @Sammo had generously given away. Absolute legend, owe you one mate. Threw on a new set of drain plugs along with it.
Having driven it a few times since, naturally the MTL alone didn't make a night and day difference but feels like it added that little bit more weight to the shifts, making it feel a tad more solid and robust. I'm sure it also offers a bit more protection than the ATF so definitely glad to have the proper stuff in there now. Might be placebo but it also seems to have made it less prone to lurching when taking off in 1st gear.
A bunch of effort for some slight 1% gains, all to get it closer to the point where I can just take the car out and enjoy driving it without fretting over something or another needing worked on. Finally getting there.