super charger gasket is called a upper plenum gasket, you'll need one elbow, but have to take the new o ring off the unused elbow and put it on the alt brackets cast elbow. they sell both in one pack.

id get some al 104 copper plugs for those mods. gaped at 0.50

for cleaning, get some degreaser, crc engine bright, purple power. then wash it off. clean it all up before the work starts.

id do the p/s pump during the lim job. your right there already with extra room even.