Jenkins kicked five penalties in each of those historic matches as the Lions produced a monumental effort to beat the reigning World Champions.
The 37-year-old, who also toured Australia with the Lions in 2001, will work as a kicking coach with the Bath squad one-day-a-week.
"Neil comes to us every Tuesday," said Bath head coach Steve Meehan. "That's been okayed by the Welsh Rugby Union and Warren Gatland."
The move, which does not interfere with Jenkins' present role with the WRU, is already bringing visible benefits for the West Country outfit.
Saturday's narrow victory over London Irish saw one of Jenkins' new pupils, 21-year-old winger Jack Cuthbert, kick the visitors to victory with three penalties at the Madejski Stadium.
"The sessions have been really helpful," said Cuthbert, who took over from World Cup winner Butch James after the South African missed three attempts at goal.
"I have been practising a lot. The management are aware of that.
"I am a fond believer that you can have style you want and if you practice hard enough you will be successful.
"I want to work on my kicking, make it another string on my bow and become a first-choice kicker."