I have '68 chevelle that has engine and trans from a '90 suburban 5.7L 350 but have been having issues with cold starts with the TBI. I have done some digging and sounds like it could be due to the IAC sensor which I intend to replace but I figured while I am at it I would like to go ahead and remove the entire throttle body and give it a good inspection and cleaning. As far as I can tell this seems pretty straight forward: remove all the sensor hook ups, remove fuel lines (in and return lines) and then basically start unbolting fuel meter housing, injector assembly, unhook throttle and then remove three bolts holding down the throttle body and pull the whole thing off.

Assuming the above is correct, a few quick questions: Is it necessary to disconnect the battery when doing this? I assume the gasket between throttle body and intake manifold will need to be replaced (any one have link to new one or can I find at local auto store, i.e. Pepboys or Advanced Auto)? Other gaskets needing to be replaced? As far as cleaning goes, just use throttle body cleaner and an old tooth brush?

Pic of TBI attached. Thanks.

 

There are some youtube videos which might help.