That engine is complicated enough without the WVO plumbing

I see some injector lines aren't clamped to their brackets (pics 18 and 19). Those injector lines are very expensive new and hard to find used. Better get them clamped ASAP. Here's your shopping list -



It also looks like you need some new injector return lines (pics 19 and 20), the braided hose from injector to injector. That should clear the puddles of fuel along injector row. Could be what you smell as exhaust in the cabin.

That bit of clear hose between the brake booster vacuum line check valve and hose to the engine shutoff solenoid (pic 22) doesn't look up to the task. Replace it with proper engine bay rated vacuum line before it melts or catches fire. Be very gentle as the entire line has to be replaced if you brake the check valve nipple.

IIRC my 93 SD had a MAP sensor tee'd into the boost signal line from the intake manifold to the ALDA. It looks like you have an overboost protection solenoid (pic 24). Temporarily remove and lines to the solenoid and hook them together. See if you get better engine performance.

None of your pictures shows the wastegate since it's best viewed from below. There should be a vacuum line coming through the aluminum sheet separating the air cleaner from the engine. It's a separate line from the one to the EGR valve (pic 15). Maybe we can see the wastegate actuator if you remove the air cleaner, airflow sensor and accordion hose to the turbo.

Sixto
87 300D