When you heat up an engine to the point of melting away the dipstick, you have probably changed the hardness of parts too.
And i really really really hope that you replaced the headbolts and also the mains bolts or atleast checked them with a vernier to check stretch.
Before the rods go back into the block, have them tested for straightness, such thermal incidents can damage these powder metal fracture type rods. Lathe shops have the tooling to check straightness.
Btw that stupid plastic is what saved the rest of the car frame, its meant to crush like paper and not channel energy into the frame/body. Older european cars and some japanese cars (like mazda) have been using front fascia made from plastic since the late 90s and early 2000s, its quite a nice design and allows the front clip to be removed for even more easier access to engine.
