Customize the "Product Assembly / Gift Wrap / ... Cost for WooCommerce" message on each product page

product_assembly_cost_message.php

<?php

add_filter( 'product_assembly_cost_message', 'my_product_assembly_cost_message', 10, 2 );
function my_product_assembly_cost_message( $message, $product ) {
	//Message on the settings: "{checkbox} Request assembly of {product} for {price}? {link}"
	$message = str_replace(
		'{product}',
		$product->get_title(),
		$message
	);
	$message = str_replace(
		'{link}',
		'<a href="https://www.info.com">More information here</a>',
		$message
	);
	return $message;
}