I'm Sorry People, i have issues with my PC, Please forgive me if i was not very clear with the pics.
The MAF is adjusted with a #5 allen wrench the red circled location in Kevins pic is the only location that has a screw hidden under a aluminum cap/plug there is no other adjustable screw on the MAF.
The throttle position sensor is adjusted by loosening up the two screws and turning it untill the desired value is reached, after that hold it in place and retighten the screws.
This information is for the 3.5ltr Gems motor, that is in my 1988 RRC. I played around with these adjustments after reading a thread on discoweb that talked about these adjustments for a 14cux ECU. The 3.5ltr uses a 13cu ECU but i experienced bettter performance as i did the adjustments. Even though DO NOT EXPECT THESE ADJUSTMENTS TO BE A WAY TO MAKE YOUR ROVER A RACE CAR IT IS NOT!!!!!! ALL IT DOES IS, IT MAKES THE ROVER MORE EFFICIENT!!! It is advisable that you write the original values down BEFORE making any adjustments, so you can go back to the original settings in case you experience problems.