Too many people have tinkered with a Compadre and I have come across several that were really messed up. It is my feeling that the very simple Compadre is best left alone by consumers, at least so far as messing with the internal trimmers, and especially trying to add a conventional 'Pinpoint' mode. If someone wants to have a detector that has a traditional, Threshold-based All metal and/or Pinpoint mode/function, then they should by a former model, like a Silver Sabre II, Silver Sabre µMAX, a Bandido series model, Eldorado, Royal Sabre, Golden Saber Plus, Pantera, Golden Sabre II, Lobo, Conquistador µMAX or many others that were offered. If current production, shop for a Cibola, Vaquero, Téjon, Lobo SuperTRAQ, Outlaw, or one of the two TID models.
I know the potential abilities of the Compadre and I am not arguing what they can do, but I will say I like more adjustment and versatility in a detector so the Compadre hasn't been a big favorite of mine. That said, there is one "modification" of a Compadre that I did like and had a chance to check one out a fellow detectorist had, and his Compadre WAS his 'Pinpointer.' This was before the big surge in hand-held pinpointing devices, and it worked deeper and provided more versatility than the conventional hand-helds we have available today.
The modification involved cutting off the back tubing from below the hand-grip. Then, remove the lower rod, and cut the middle rod very short. Just enough to extend from the upper rod after the rod-lock was tightened. The 'isolator' section was used and affixed to the shortened middle rod, and a 4" search coil was added with the coil cable shortened to not be in the way and hard-wired.
This resulted in a short-length detector with a pistol-grip, and a 4" Concentric coil mounted. You could just thumb the On/Off knob to the minimum setting for All Metal detection [size=small](it has the ED180 Disc. circuitry)[/size] and use it to 'pinpoint' ferrous and non-ferrous targets. It also provided the variable Discriminate setting should the searcher want to use an adjustment to help deal with some small iron trash when pinpointing. Many early Pinpointers, and some offered still [size=small](like the Auto-Max, etc.)[/size] were/are kind of bulky and awkward, and this little modified Compadre was shortened enough to be carried in a bigger-size finds pouch, and some even made a little 'holster' or 'sheath' to carry it.
Other than making your own useful Pinpointer out of a Compadre, I think the best idea is to just acquire a better, more versatile detector that will provide that feature. Otherwise, Tesoro's have always been very functional in the slow-sweep/quick-response and recovery category to make short crossing patterns to isolate most targets.
Monte