Hi and welcome to mightyram. The Mikuni is not for the faint of heart but it is one of the things that restricts the engines potential (that and the factory tune and the emissions garbage). Look up the Weber threads on the site - it has been extensively covered and is probably the single most popular upgrade for these trucks. First point of call - http://www.mightyram50.net/vbulletin...carb-Becareful!!!!!!!!!!!!

Don't get duped into buying a 'licensed copy' (POS knock off). Look through the "Tuning and Smog" section for the various threads but you will need:

High volume, low pressure electric fuel pump (ebay - Carbole 42S pump is a good option)
Weber adapter kit
Auto kickdown cable kit
Weber 32/36 DFEV (throttle linkages are the same configuration as the factory carb, electric choke)

You will need to block off the coolant hose connections for the factory water operated choke set up (easy job). Can't find exactly what you want, ask questions. Members will hook you up with links to info on the specifics.