200-4R Behind a 340 and Reid Bellhousing Build

thank you.we have a 68 cuda but I also have an 84 monte carlo with a 700r.the monte is set up so that it will only lock up if I use the toggle switch.and it will only lock up in 4th gear or OD on the shifter indicator.this is how I like it and how im used to it.if I forget to flip the switch it goes out on its own when it goes to lower gears.im only reminded that I forgot once it goes up to 4th again and bogs.this is no problem and I just flip the switch(rarely happens)im having a 200 built for another project and I weant it to work the same.the rebuilder says it should only lock up in 4th and he only has one wire coming out just like my 700r.i just want to make sure it will go out of lockup on its own when it shifts to a lower gear.now is the time to make sure while its still on his bench and empty of fluid.
thank you!