Recon (1982)

From back cover:

"Snoopin' and Poopin'"

"Four to twelve men operating deep in the bush of Vietnam. Outnumbered. With only wit, skill, & raw courage between them & violent death. Looking for the Viet Cong in his jungle sanctuary; then dumping on him. Snooping and pooping, the recon missions of the LRRP, SOG, SEAL, Delta, PRU, and Phoenix."

"Recon recreates 34 operations using a percentile role playing system that features a unique mapless terrain generation, for faster play and simpler preparation. Recon can be played with 20mm Vietnam figures already available!"

"Special artillery, airstrike, and helicopter gunship rules let you call in anything from miniguns to napalm."

"Begin your mission by inserting via chopper, river patrol boat, HALO parachute drop, or underwater using SCUBA."

"Continue your character's career after 'Nam as a soldier of fortune with the 19 missions also in this book."

One way to tell if you have a second edition (as it's unmarked as such) is on the inside front cover there's a section entitled "Stay A LRRP, Stay Alive" thanking people for voting for Recon for the "Best Roleplaying Game" for the the H.G. Wells awards in 1982. Also has a sales blurb on the inside back cover about current and upcoming releases