How do I create custom purchase conversion in Fb toFb pixel code for Orderform to send dynamic value in usd to fb

Hi, I built an e-commerce funnel. I have connected fb pixel and capi on my workspace setting. I want to setup a custom purchase conversion for the orderform, I want to send purchase value in usd to fb for the orderform only. How do I do it? Any ideas?

Ai says use following code in orderform footer. fbq('trackCustom', 'FEOrderFormPurchase', {
value: {{order_total}},
currency: 'USD'
});

How do I ensure the dynamic purchase value is sent dynamically to Meta. Because I have 7 different price points in my order form including orderbumps.

Any cool idea how you did it to run fb campaign and optimise for orderform purchase event along dynamic conversion value

I am stuck 😔 with this from last month, can anyone remove this blocker.