Hi Cemlyn, a Commer middle seat is only bolted to the engine cover so you would still need some method of securing the baby seat. You could pick up the drivers and passenger seats seatbelt anchor points to fit something that the baby seat could attach to, it's been done before so no reason why you couldn't do the same, but have you thought about adapting a seat from another classic - like a Mini. It's not too big and some brackets welded to the frame would suffice to secure it to the engine lid, there must be loads of other seats out there that would fit the bill. The other option would be to use long straps secured through the floor with spreader plates on one of the rear benches, the baby seat could face forward leaning against the side of the cupboards on either side and the long straps would come up from below and hold things together, trouble is it wouldn't be easy to get to the little one from the cab:I I know Clarabel has this mod.