After replacing my floor and everything, i've come to realise that the lower firewall/healboard bolts that go through the front subframe are now spaced apart. Can I just leave them out or should i use some washers and fit anyway??

They're kind of important.
Put them back, the bolt should pull the two parts together.

Loosen the other subframe mounting bolts, then you should be able to get all of the holes to line up. And yes they are important, they hold your car together.

After reading my post, I realise how this sounds. But I've got the two straight up vertical bolts through the sub frame and floor, and all others, its just those couple on the diagonal part of the firewall. I don't think it will be able to pull the gap in without bending the floor.

Forgot to add, because i had to cut so far up when replacing the floor, I have to re drill all the holes as well.

I think the simplest answer is if they aren't needed the factory wouldn't have put them in and saved themselves eight and a half cents.

If you're waiting for someone to post "leave them out" as an excuse to shift the blame if
something goes wrong then you have the wrongg idea.

Can you post a picture so we can see? You might be able to shrink the metal using heat and then quench it with water?

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