Parkwood, my trans is a Bowtie Overdrives 700-R4 Level 2 with their 2400 stall high performance converter. I don't have a vacuum switch, but the trans is wired for converter lockup in 4th gear. It unlocks with a brake pressure switch. I also have a toggle switch on the dash to lock it up in the other three gears. I do have the wiring diagram that incorporates both manual toggle and vacuum switches. It's been a while since I worked on the wiring, so I'll have to take a look. Thanks for the info.