I would inject the birds with your injection flavor of choice then rub the bird or birds down with a light coat of yellow mustard then a good dry rub, this will retain the natural and injected juices. Since pheasants are smaller, you don't want them to dry out and you don't want to over smoke them either. Go easy on the amount of time the smoke is applied and try using a milder wood like apple or cherry. Put a meat thermometer in the breast and remove once it hits 165 degrees then wrap or cover in foil and let them sit for 15 minutes so the juices can redistribute.
Now youve hit a soft spot!!! I love...and I mean love....shootin critters and smokin em...Pheasant is one of my favorites. I ve done it several ways,but my favorite is to smoke it whole. I use melted butter and garlic salt as a basting/ mop. I too bring the birds up to about 165..w/thermo in the breast....Start off with the smoker at about 215-230. Apply mp every 30-45 min. Once your bird gets up to 130 or so crank up the smoker to about 300 to toughen up/crisp the skin. Also like Bigdaddy stated....wrap in foil,towels,and put in a cooler to keep warm for about 15 to 20 min...and prepare to chow down!!!
Good luck...youll love it!!!