In the pdf document for changing the gateway, there is an instruction to delete the two existing server behaviors for authorize.net and paypal. Then the next instruction is to delete a selection of code on the confirm.php page between specific numbered lines of code.
There is a note that if you have already made changes to the page code then the beginning line number of that code may be in a different possition on the page.
Some of the code that needed to be deleted, was not between the first and last lines of code to be deleted. So I searched the code on the page and was able to locate the lines that did not get deleted.
That solved the error problem with inserting the local checkout with FirstData
What is the fastest way to intigrate the FirstData API and Certificate?
and if I the FirstData Payment Gateway integration, will I loose any of the functions of the powerstore?