have you got the correct jumpers for the ROMs you are using?

also see acid leakage still on the board, this will travel, needs to be completely gone.

the solder on the rear of board for Q5 looks close to neighbouring traces, i'd be cleaning that up.
some of the pins on the 6800 U9 look to be quite tarnished/oxidised, i'd be cleaning them up.

you may have a short/eaten away trace under the U8 socket, personally i'd be replacing both the U7 & U8 sockets with socket strips.

VR1 is an 8.2V zener.......i'd be replacing that, honestly with all those components in the reset section 40 odd years old, i replace them all and raise R11 the 82ohm up about 20mm.

have you seen with a logic probe or scope pin 40 go from low to high on the 6800?

shorting pins 40 to 39 should turn off the LED, if it doesn't the problem looks to be the reset circuit.

i may have missed something, but how do you know the reset is working?

the 6800's you are using in U9, can you confirm they good by them working in another mpu?

it may be nothing, but in your first post, on the rear of the board where pin 40 and 39 of U9 the 6800 join to the top header J5, it looks like a possible short?