I’m going long sleeve thermal base layer, short sleeve jersey, thermal gloves, bibs, shoe covers.
No jacket, no vest - in ~3 hours at race pace I will cook in all that, and I’d rather be too cool than too warm as the race goes on. The rain should subside in the first hour, and the air movement will dry everything better if I’m not as insulated in layers.
Game day decisions - bibs vs tights vs both (I dislike knee warmers), helmet cover vs cap, eyewear - clear vs amber.
Probably will go with cap because I’ve never tried the helmet cover and a race is no time to be field testing new gear.