R&D/facelift bug in new beta version

1960s - pushing exhaust tech to get two-way cat early for my dirty 8V vans
1972 - got the tech; R&D shows that im getting three-way cat in 3 years.
Trying to make a new facelift of the old engine with two-way cat, but it doesn’t show up in the list:


When i make a new engine family(same exact engine configuration) two-way cat shows up.
Other techs have been working fine, as far as i can tell only this exhaust tech bug.
Or am I doing something wrong?

Edit: Solved! Turns out you can’t put a two-way cat on a car that runs on leaded fuel.

New family: