'79 Rabbit couple questions (speaker for stereo and clutch)

Hey there guys. Just bought a '79 Rabbit with a 1.9 conversion and its got a veggie oil conversion for 1500$ 4 door. Really great condition! Head liner isnt ever sagging! Couple small issues but most things I know how to fix are waiting on the amazon guy to bring me parts.

4 questions total for you guys.

1: My rabbit only has one speaker, its center of the dashboard up on top. Anyone know the size and if I access it from the bottom?

2: When I let off the clutch, it squeels a bit. I'm thinking it may be time for a clutch replacement. This has a 5 speed. The clutch also has to be let ALL the way out to engage, is that normal on these? I had a caddy that seemed a lot less sloppy. Would adjusting the cable remedy it?

3: I get FANTASTIC power. Seriously, I was going 80 on the highway absolutely no issue (verified by phone gps since speedo doesnt work) but I was leaving a bit of smoke behind while cruising along. On the injection pump I know I can adjust the fuel screw, would this clear the smoke up?

4: Last but not least, I seem to have something sticking. When I let off the gas, it holds rpm for a few seconds before losing power like it should. I checked the throttle body and it is a very smooth action. Any ideas on what to look for? Could it be related to #3?

Appreciate it guys! Also, if anyone is in NC and wants a full veggie conversion kit for a 1.5 1.6 or 1.9 I'll sell you the complete setup thats on my car for 400$. Comes with an 11 gallon tank and everything! I know I'll never use it and its just more places for leaks to pop up.