if it was me
I would know from the bid and contract
what is needed and called for
the client sent out specs for the bid
then accepted the bid
and both parties signed a contract
(should be looked over and same as the bid papers)
a change from bid to contract should be taken into account and change the price
(but if a party missed the change...oh well...stuck and eat the loss, fulfill the contract)
a change from the contract voids the contract
and must be dealt with as new contract status
meaning new pricing
just my thoughts
as far as tacks go,
weld to 1/2" of the tack and cut or grind it out the tacks
sincerely,
Kent