How the fark did you do that??? As long as all the bolt mounts are ok and its only a crack I wouldnt worry too much. Just make sure you get all the crap out of there before you put it back together
Do not use the high pressure hose on the engine and electrics. Just sorta rinse with water gently. If you use heaps of pressure you may well get water into all the small electric connections.
I must say when I did this a month or so ago it made a big difference just like others have said. Kinda tempted to go down and do it again.. but........No
Make and size? Crappppp, 8 inch. ← They did change the level of crapness.. They used to be made out of paper and now they're plastic.. I went through 2 of the paper ones now have the plastic and still all good