I am having a hard time getting any confirmation on this.

For those with Non I/C motors...Can a valve adjustment be done on the 89 to 91 NON I/C trucks WITHOUT removing the intake horn?

I just need to know whether I must remove it and have new plenum/grid heater gaskets on hand or not. Not sure if there is any clearance issue associated with leaving it on (valve cover R&R, room to adjust etc).

 

IIRC you dont have to, just loosen the bolts on the horn a little so you can sneek the valve cover by.