I agree with the comments regarding grade 8 bolts.

I have over the years restored and otherwise maintained countless early vehicles,chiefly pre-29, and chassis rivetting was done of a purpose.

My Vauxhall is a prime example,in all essentials it is an Edwardian design,deriving from the Prince Henry 3 litre,with a correspondingly flexible chassis.

While the Vauxhalls could not be beat in straight sprints and hill climbing their somewhat flexible chassis robbed them of any easy handling above 75-80 MPH.

many have tried welded members but the penalty was cracked joints as if in rebellion to the welding.

I have found that grade 8 bolts,welded at the nut-bolt joint are more than sufficient for durability and flexibility,my InterState being a prime example.

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