Ranking 2 Domains in different Country

Hi, we have one website which is ranking very well in Australia with a .com.au domain. We want to expand the business across to America and we are planning to launch .com domain.

Will it be sufficient to replicate the exact website and launch it as .com domain but change:

• Meta data for main top 20~ visited pages
• Remove any local traces from .com.au domain and use America’s eg: address, phone numbers
• Change the spellings, grammar accordingly to American English

The website has at least 240 blog posts so they will be replicated as they are, 10 services pages which will be changed according to above. The overall content will not be re written like any paragraph or such.

Will this be a duplicate issue? any content penalty? and would this be a good way to approach this solution? If not, please suggest any methods to approach this. Any help would be grateful for. Thanks!