gas small coming from exhaust after tune up on 1993 Chevrolet G Series Van (G20)

changed plugs, filter,etc etc. Removed ditributor and checked rotor. put back in distrib. could a slight change in position of distrub or rotor cause timing to be off that would cause gas smell? gaps on plugs i think set at 44. what do YOU normally set your plug gaps at???? and should i have timing reset. fuel filter fine, canister ok...???

spark plug gap is usualy 35 but it still wont give you a fuel smell check to see if you have a fuel leak somewhere If you had the distributor out then you need to check your timing I would like to know why you had the distributor out