Rough Idle Problem -- pn number help

["mikesoft" <mikesoft@europa1.conwaycorp.net>]

My '88 80Q seems to have a rough idle running sometimes at a 
very low rpm. Sometimes the car will stall for example when 
stopping say at a stop sign suddenly with the gear still engaged
clutch and brake depressed, shifting to neutral seems to solve
the problem. I have just gotten my A/C fixed and somehow the 
rough idle is a little better though I can still detect some surges
while the a/c is on while the car is moving

I suspect that the cause of the problem might be a cracked hose leading 
to the valve intake, there are two hoses and the lower one appears
to be the one with the problem. I was wondering if there could be 
any other causes other than this hose that I could check. And I  
would also like if possible to get the P/N and actual name of the 
hose. Also is replacement a labor intensive task ? Would it be a 
DIY kind of job ? Thanks 

Mike Theuri