USMC6282 has posted photos of his Remington 870 with Magpul upgrades on Remington 870 forum:
So a few weeks ago i purchased an old remmington 870. looked up the serial and found that it is older than i am. it’s a 1979 wingmaster with the barrel cut to 18.5″. when i first recieved it the safety was stuck in the off position, and it was a little (really dirty in my standards) condition. upon coming home i tore it all apart and found cosmoline on the bolt and trigger group. its weird because i figured the previous owner would have cared for it. so did a full inspection, complete cleaning, repaired the safety, and put it all back together. then i didnt like how the worn bluing looked so started to sand the reciever and finally decided to hand polish it starting at 80 grit and progressing to 3000 grit wet/dry and finally polishing paste. then i noticed the stock was cracked in multiple spots so that had to go. all in all i purchased the gun for 200 dollars and put 250 into it.
Magpul MOE foregrip 30
Magpul SGA stock 99
Magpul MS3 QD sling 50
Magpul GD grommit for SGA stock 14
GG&G follower 30
Oversized safety 15
The barrel is what the bluing looked like before and the reciever is after polishing. the barrel recieved a light sanding and rustoleum camo flat black for temporary paint until i get the barrel parkerized.
this is just after the polishing job